This is a request for funding a Developing Center for Intervention and Services Research (DCISR) in response to PAR 01-090. This new center will focus on patients who present in primary care with medically unexplained physical symptoms (MUPS). MUPS (e.g., unexplained pain, numbness, gastrointestinal symptoms) comprise a very common clinical presentation for disabling psychiatric disorders in primary care settings, such as depression and anxiety. The name of this new Developing Center will be the "MUPS in Primary Care Research Center" (MUPS-PCRC.) The center will build the necessary cores (e.g., operations, methods, training) and infrastructure for developing an innovative services research program in primary care concerning this population. Furthermore, the initial studies planned for the MUPS-PCRS will relate to lower socioeconomic status Latino and African-American patients, due to the well-documented disparities in mental health care for these populations. The faculty of MUPS-PCRS will also explore the effectiveness of a culturally- competent, collaborative stepped-care model for treating primary care patients with MUPS, while examining how patients, family members, physicians and behavioral health care specialists accept this model. At least four pilot studies are planned, in consultation with an external advisory board of leading researchers, and apace with research infrastructure implementation. These studies will gather preliminary data on different stages of the collaborative stepped-care model. One study will focus on development and testing of specialized videos and other educational materials to be used in the first stage of the model, whereas another study will focus on the effectiveness of cognitive behavioral therapy (CBT) as a second stage treatment strategy and as a way to facilitate behavioral health care referrals. Two other studies concern alternative third-stage treatments for patients who do not respond well to CBT: a) heart rate variability biofeedback for the treatment of residual depression and somatic complaints;b) interpersonal therapy. The expectation is that preliminary data collected in the various studies conducted in the first few years of Center operations will inform the design and planning of several larger-scale investigator -initiated grant applications from MUPS-PCRC faculty and trainees.